Electron-beam writers

The mask-making process consists of generating the pattern of the circuit on a chrome-covered quartz plate coated with a resist film. There are four types of equipment used in writing mask optical pattern generators, electron-beam writers, focused-ion-beam writers, and laser writers. Lithographic exposure of the resist-coated, chrome-covered quartz plate involves the repeated exposure of the circuit pattern with a stepper or a scanner. In earlier times, lithographic... 

In general, laser writers offer some unique advantages. With multiple laser beams (up to 32 in some systems), these systems are capable of high throughput and are therefore considerably faster than their electron-beam-writer counterparts. They are also more accurate than electron-beam writers because they are more stable, a consequence of the facts that electrons are very sensitive to magnetic fields and also tend to scatter. The very small effective address unit is useful for fine adjustment of line widths on the mask, which makes it easier to implement optical proximity correction schemes in these masks than in masks produced from other mask writers. Furthermore, laser writers operating at 364-nm and... 

Typical optical and laser writer mask-making resists include 895i from ARCH (formerly OCG and now Fuji Films) and iP3500 from TOK for 364-nm exposure systems. Typical resists for electron-beam writers include poly(butene-l-sulfone) (PBS) developed at Bell Laboratories, EBR-900 Ml (novolac-based resist) from Toray Industries, ZEP 7000 from Nippon Zeon, and KRS-XE from IBM. ... 

Furthermore, we widened the scope and potential application fields using different activation methods. Low-pressure and atmospheric-pressure plasma sources as well as vacuum UV lamps were used for large area exposures and, in combination with shadow masks, to produce patterns in the micrometer to millimeter range. Exposures at LIGA beamlines were used to produce bulk structures and electron beam writers to generate arbitrary high-resolution structures. 

While the original pattern-generation tools of the early 1970s were optical systems, in 1974, AT T BeU Laboratories introduced an electron-beam direct exposure mask-making system called MEBES," which was subsequently licensed to ETEC for commercialization. By 1980, electron-beam mask writers became... 

Similar to electrons in e-beam writers, focused ion beams could possibly be used to write arbitrary radical patterns for subsequent graft polymerization. However, such an approach has seemingly not been reported in the literature. It is assumed that analogous to e-beam... 

We can say that such a static device is a U( ) unipolar, set rotational axis, sampling device and the fast polarization (and rotation) modulated beam is a multipolar, multirotation axis, SU(2) beam. The reader may ask how many situations are there in which a sampling device, at set unvarying polarization, samples at a slower rate than the modulation rate of a radiated beam The answer is that there is an infinite number, because from the point of the view of the writer, nature is set up to be that way [26], For example, the period of modulation can be faster than the electronic or vibrational or dipole relaxation times of any atom or molecule. In other words, pulses or wavepackets (which, in temporal length, constitute the sampling of a continuous wave, continuously polarization and rotation modulated, but sampled only over a temporal length between arrival and departure time at the instantaneous polarization of the sampler of set polarization and rotation—in this case an electronic or vibrational state or dipole) have an internal modulation at a rate greater than that of the relaxation or absorption time of the electronic or vibrational state. 

---